Should I use R19 or r21?

Both come in rolls and are installed the same way. R-21 insulation is more efficient at preventing the transfer of heat, but it costs more per square foot. Construction companies often use R-19 as the standard insulation and may offer R-21 insulation as an available upgrade to buyers.
Takedown request   |   View complete answer on hunker.com


Is higher R insulation better?

The R-value for insulation is a way to measure how much resistance the insulation has to heat flow. The higher the R-value, the more the resistance and the better the material is at insulating a home.
Takedown request   |   View complete answer on forbes.com


Is R19 insulation enough?

There is a direct relationship between the amount of insulation and the amount of heat transfer. The bigger the R value, the better the insulation is at slowing down the heat transfer. So R19 is better insulation than R13, and R30 is better than R19. The larger the R value, the better the insulation value.
Takedown request   |   View complete answer on patch.com


What is R19 insulation used for?

The Basics of R19 Insulation

R19 Insulation is any type of insulation that achieves that specific R-Value measurement of R19. R-value is used to judge thermal insulation performance and the higher the number, the better the product's insulating ability. So R19 has better insulating ability than R13.
Takedown request   |   View complete answer on havelockwool.com


Which R-value should I use?

Depending on where you live and the part of your home you're insulating (walls, crawlspace, attic, etc.), you'll need a different R-Value. Typical recommendations for exterior walls are R-13 to R-23, while R-30, R-38 and R-49 are common for ceilings and attic spaces.
Takedown request   |   View complete answer on jm.com


Insulation R-VALUE - What is R-Value?



Why is R19 thicker than R21?

R19 is 6.5″ thick whereas R21 is 5.5″ thick. Thinner by one inch and yet 2 points higher in R value. The common explanation as to why this is so, is that the R21 insulation is said to be “more dense”.
Takedown request   |   View complete answer on greenbuildingadvisor.com


How thick is R21 batt insulation?

5½ " thick R-21 EcoTouch® insulation delivers 19% more R-value than compressed 6¼ " R-19 Fiberglas™ insulation. The kraft facing on this insulation will burn and must not be left exposed. Install facing in substantial contact with the finish material. Protect from open flame or other heat source.
Takedown request   |   View complete answer on www2.owenscorning.com


Is R-19 good for walls?

Although the U.S. Department of Energy rates R-13 insulation as "good" for use in walls in southern areas of the country, it rates R-19 insulation higher, designating it as "great." That is because R-19 insulation provides more thermal insulation than R-13 does.
Takedown request   |   View complete answer on hunker.com


What R-value insulation should I use in my garage?

Exterior Garage Walls

Typically these will be constructed from standard 2-by-4 studs which will define the amount of insulation that you can have installed. You should be targeting an R-Value of R-13 or R-15 in these areas to properly maximize your insulation in this application.
Takedown request   |   View complete answer on danleys.com


What R-value should I use in my attic?

The higher the R-Value, the better the thermal performance of the insulation. The recommended level for most attics is to insulate to R-38 or about 10 to 14 inches, depending on insulation type.
Takedown request   |   View complete answer on energystar.gov


Can you over insulate a house?

It is possible to over-insulate your house so much that it can't breathe. The whole point of home insulation is to tightly seal your home's interior. But if it becomes too tightly sealed with too many layers of insulation, moisture can get trapped inside those layers. That's when mold starts to grow.
Takedown request   |   View complete answer on reenergizeco.com


What is the best R-value for 2x4 walls?

They are available in widths suited to standard spacings of wall studs and attic or floor joists: 2x4 walls can hold R-13 or R-15 batts; 2x6 walls can have R-19 or R-21 products.
Takedown request   |   View complete answer on allfloridainsulation.com


Should you want a high or low R-value in your home?

Typically, a higher insulation R rating means better climate control and better energy efficiency for your home. A higher insulation R-value usually means a higher price point as well. For every type and material of insulation, check the R-value per inch of thickness that the manufacturer has listed.
Takedown request   |   View complete answer on homedepot.com


What is the best R-value per inch?

Vacuum insulated panels have the highest R-value, approximately R-45 (in U.S. units) per inch; aerogel has the next highest R-value (about R-10 to R-30 per inch), followed by polyurethane (PUR) and phenolic foam insulations with R-7 per inch.
Takedown request   |   View complete answer on en.wikipedia.org


What is r20 insulation used for?

Description. Use this Johns Manville fibreglass insulation to cover your walls and ceilings in basements, crawl spaces and attics. Offering a thermal resistance of R-20, this 19 in x 48 in insulation batt provides moisture control in exterior walls.
Takedown request   |   View complete answer on rona.ca


What is a good R-value for interior walls?

Depending on the insulation properties of the existing wall, in general the R-values of the renovated walls can be between R-19 and R-22 (0.25 to 0.30 W / m² K) - without additional risk to the structure.
Takedown request   |   View complete answer on foursevenfive.com


What insulation is best for soundproofing?

When soundproofing is your goal, your best options out there are fiberglass insulation and blown-in cellulose insulation. Both materials are incredibly good at their jobs; they insulate incredibly well but also have the coveted noise-reducing properties that many homeowners are seeking.
Takedown request   |   View complete answer on andersoninsulationme.com


What's the best insulation for walls?

The best insulation for walls when it comes to new build homes or remodels is going to be Nu-Wool, foam board, or open cell spray foam.
...
Cons:
  • Open cell spray foam is an expensive option for insulation.
  • Spray foam can't be installed as a DIY project.
  • Some brands of spray foam have an odor when installed.
Takedown request   |   View complete answer on retrofoamofmichigan.com


Can you get r21 in 2x4 wall?

When you choose to insulate 2-inch by 4-inch walls to achieve an R-21 value, there are options available to you. Only one option is appropriate for the average do-it-yourselfer to try and tackle, and that is polyurethane rigid foam. This material is easy to work with, and installation is not difficult.
Takedown request   |   View complete answer on homeguides.sfgate.com


What is the highest R-value for a 2x6 wall?

Thermal Control

The installed insulation R-value for 2x6 fiberglass batt ranges between R-19 and R-21. When blown or sprayed cellulose insulation is used, the R-value is typically R-20 for 2x6 walls.
Takedown request   |   View complete answer on buildingscience.com


What does the R mean in R-value?

The R stands for resistance to heat flow. R-value is universal across all insulation products, so the measurement will mean the same thing no matter who sells or manufactures the insulation. R-value is even consistent across different types of insulation.
Takedown request   |   View complete answer on rinaldis.com


Can you use R21 on ceilings?

Owens Corning R21 Insulation 15 x 93 Faced Fiberglass Batt. OC Daced Formaldehyde-free ™ fiberglass insulation is excellent for reliable thermal as well as sound control. Owens Corning Faced insulation is easily offered in pre-cut batts to fit common wall surface and ceiling areas.
Takedown request   |   View complete answer on pacificinsulationsupply.com
Next question
What if your spouse has HPV?